Abstract

We use near-infrared interferometric data coupled with trigonometric
parallax values and spectral energy distribution fitting to directly
determine stellar radii, effective temperatures and luminosities for the
exoplanet host stars 61 Vir, rho CrB, GJ 176, GJ 614, GJ 649, GJ 876,
HD 1461, HD 7924, HD 33564, HD 107383 and HD 210702. Three of these
targets are M dwarfs. Statistical uncertainties in the stellar radii and
effective temperatures range from 0.5 to 5 per cent and from 0.2 to 2
per cent, respectively. For eight of these targets, this work presents
the first directly determined values of radius and temperature; for the
other three, we provide updates to their properties. The stellar
fundamental parameters are used to estimate stellar mass and calculate
the location and extent of each system's circumstellar habitable zone.
Two of these systems have planets that spend at least parts of their
respective orbits in the system habitable zone: two of GJ 876's four
planets and the planet that orbits HD 33564. We find that our value for
GJ 876's stellar radius is more than 20 per cent larger than previous
estimates and frequently used values in the astronomical literature.